SDG 6:
ensure availability and sustainable management of water and sanitation for all
- By 2030, achieve universal and equitable access to safe and affordable drinking water for all
- By 2030, achieve access to adequate and equitable sanitation and hygiene for all
- By 2030, improve water quality by reducing pollution, eliminating dumping and minimizing release of hazardous chemicals and materials, halving the proportion of untreated wastewater and substantially increasing recycling and safe reuse globally
- Protect and restore water-related ecosystems, including
mountains, forests, wetlands, rivers, aquifers and lakes
WHAT DO URBAN WATER SYSTEMS DO?
- Ensure safe drinking water supply
- Treat wastewater
- Manage stormwaters that cause flooding
COMBINED STORMWATER- SEWER SYSTEMS
- Most of the island of Montréal is serviced by combined stormwater-sewer system
- Drainage pipes beneath each street collect stormwater and transfer it to the city’s interceptor pipes.
Stormwater
refers to rainfall that remains on the ground’s surface and flows to water bodies
20 TH CENTURY STORMWATER MANAGEMENT
the goal
To remove stormwater as quickly as possible and minimize flooding through systems of pipes and channels
20TH CENTURY STORMWATER MANAGEMENT
Minor and major conveyance systems
Minor systems remove minor and frequent rainfall (storm sewers, ditches)
Major systems remove heavy but infrequent rainfall (streets, large channels)
20TH CENTURY STORMWATER MANAGEMENT
challenges
Displacement of floor risk to downstream communities
UR B A N I ZAT I O N IMPACT S NAT UR A L WATER CYCLES
how
Buildings and impervious surfaces alter natural water flows.
Rainfall is redirected to sewers instead of recharging in the ground.
Untreated stormwater can pollute waterways and damage aquatic habitat.
Higher volumes of stormwater entering waterways can increase erosion.
Flooding can result if rainfall exceeds capacity of stormwater drains.
WHAT CAN CITIES DO?
Cities can integrate stormwater-sewer separation into routine
maintenance
INTEGRATED STORMWATER MANAGEMENT
goes beyond infrastructure design
Accommodate urban growth and protect natural resources
Be ecosystem-based
Mimic the natural water cycle
SUSTAINABLE URBAN DRAINAGE SYSTEMS
Frames stormwater runoff as a value natural resource that can benefit urban environments
- Infiltration: aims to reduce the amount of water entering stormwater systems through absorption or evaporation
- Attenuation: aims to slow the rate of runoff flow so it is released slowly
- Filter pollutants
CHALLENGES FOR ACHIEVING SDG 6
- Ensuring supply and access
- Providing affordable services
- Guaranteeing service quality
water stress and what is it
A significant number of cities are water stressed
25%
they rely on surface or groundwater sources that are under stress
WESTERN U.S. DROUGHT
Southwestern US is experiencing its worst megadrought in over 1,000 years.
Creates tension between water uses, particularly agricultural and urban users.
A number of cities have introduced water rationing or banned non- essential uses like irrigation of ornamental landscape
Challenges for infrastructure systems
Historically, water and sanitation systems were built by governments.
the link between disease and urbanization
Disease eradicated becomes central issue for social reformers.
Diseases have high transmission rates – 50% of working class people die before their 50 th birthday.
Late 19th century becomes a turning point for urban infrastructure: construction of the London sanitation system.
22,000 km of local and main sewer lines, pumping stations to move sewage downstream.
challenges for ensuring affordability of water services
In places lacking piped drinking and wastewater systems, households rely on water trucks or bottled water.
- This is very expensive! Far more so than piped water.
- The lowest income urban residents tend to pay fees for water access.
Low accessibility to high quality and safe drinking water carries a particularly high burden for women and children.
which ones
- Distances traveled for water
- Risks to personal safety
- Missed school
Communal toilets are sometimes the only sanitary facility available
what are the consequences of this
- Lack of privacy, safety, and dignity
- Don’t accommodate the needs of menstruating or pregnant people, people with disabilities, etc.
- Lack of private toilets in schools is a major reason that girls miss school in many regions.
SOLID WASTE GENERATION
strongly linked to wealth and consumption
People living in central, wealthy neighbourhoods are more likely to have waste collection services.
Poorer neighbourhoods are more likely to dispose of their waste informally.
Waste disposal has a huge impact on water quality.
